Design Of Bionic Double-rods Climbing Soft Robot

Soft actuators and soft robots have become the focus of current academic research because of their flexibility,continuous deformation and good human-machine interaction.These characteristics,which are better than rigid robots,largely depend on the design of materials,driving modes and the structure of soft actuators.For the design and manufacture of soft robot,bionics plays an important role in this process.The other key design elements include:bionic concept,soft material design,driving form design and bionic structure design.The design inspiration of the bionic two-rods climbing soft robot studied in paper is derived from the biological behavior in nature-the "three-step" movement form of the inchworm.The soft robot was designed and tested by combining soft materials such as polypropylene,rubber and vinyl acetate polymer(hot melt adhesive),inflatable drive form and folded bellows structure.At the same time,the robot follows a modular design principle,consisting of four identical bending soft actuators and one telescopic soft actuator,capable of vertical or horizontal climbing on parallel rods.By analyzing the deformation theory of bending soft actuator and telescopic soft actuator,the "three-step" climbing gait and control strategy of robot like inchworm are designed.In this regard,this paper focuses on the impact of structural design parameters and external environmental factors on the robot performance,as follows:(1)A new two-pole climbing soft robot is presented.As the execution components of the robot,the structure design parameters of the bending soft actuator and the telescopic soft actuator have a crucial impact on robot.The bending soft actuator and flexible soft actuator are made of polypropylene with high cost performance.(2)There are two design forms of extendable executor: fully wrapped and annular distributed.Compared with annular distributed,fully wrapped executor has stronger extendable effect and can improve the climbing efficiency of robot by nearly 2 times.(3)The driving frequency of the controller and the diameter of the climbing rod will also affect the climbing performance of the robot.The robot can achieve the highest driving frequency of 0.83 Hz,the lateral climbing speed is about 18mm/s,and the diameter of the climbing rod is in the range of 10mm-35 mm.When the diameter is 25 mm at the current size,the highest efficiency can be achieved.This soft robot is not only simple in structure,but also low in research and development cost.Bionic two-rods climbing robot can be used in deep water,nuclear power plant and high voltage cable scenarios because of its waterproof,insulation and radiation resistance that cannot be matched by rigid robots.Moreover,the executive parts of soft robot can be used as soft gripper in manufacturing industry due to its good adaptability,so objects can be sorted safely without any complicated control such as force sensor.In addition,the design of two-rods climbing soft robot is deeply integrated with the bionic design concept,which is expected to bring more design inspiration to the pre-research products of bionic soft robot.